Abstract: Giant pandas depend on bamboos for food, making these plants vital for their sustenance and survival. This study was carried out in Foping Nature Reserve, Shaanxi Province, China and analyzed the structure and nutritional value of two bamboo species present in the reserve at different elevations. In this region of the Qinling Mountains, the two staple food bamboos are Bashania fargesii and Fargesia qinlingensis. Our results indicate that: (1) elevation had a significant effect (p0.05) on both the height and basal diameter of bamboos, thus strongly influencing the mean value and variance (uniformity, evenness, skewness and kurtosis) of these two characteristics in bamboo forests at different elevations. (2) The significant effects on bamboo nutrition by elevation varied with seasons (p=0.02 for crude protein and total sugar in spring; p=0.01 for crude fiber in summer; p=0.04 for crude protein and crude fiber, and p0.01 for total sugar in autumn). The two bamboo species we studied also differed significantly with respect to how nutritional value is distributed among the leaf, branch, and culm parts of the plant (p0.05). (3) Because elevation and seasonal conditions both affect bamboo nutrition, pandas adapt their feeding strategies accordingly: in summer, they go to higher elevation areas, and in the other three seasons they prefer lower elevations. Our research sheds light on the relationships among elevation, nutrition, and bamboo structure, along with giant panda migration patterns. In addition, this study provides a theoretical foundation for decision-making with regard to food provision for captive giant pandas. It also provides scientific support for policies to protect wild pandas and the regulation of human activity inside conservation areas.

Key words: giant panda, staple food bamboo, bamboo nutrition, bamboo structure, seasonal migration

摘要： 大熊猫主要采食竹子，因此主食竹对大熊猫生存具有重要的作用。在秦岭的佛坪地区的大熊猫主要取食巴山木竹以及秦岭箭竹。本文研究了海拔对这两种竹林的结构与营养含量的影响以及海拔与大熊猫季节性分布的关系。结果表明：（1）海拔对竹林基径、株高有显著影响（p0.05）；整齐度、均匀度、基径和株高分布的偏度值和峰度值均随海拔变化而变化。（2）海拔对主食竹营养含量的显著影响随季节而变化（春季粗蛋白和总糖p=0.02；夏季粗纤维p=0.01；秋季粗蛋白p=0.04、粗纤维p=0.04和总糖p0.01）。每个竹种在叶、枝、杆三个部位间的营养均有显著性差异（p0.05）。（3）海拔对竹林结构及营养的显著影响决定了大熊猫对主食竹的取食策略，夏季在高海拔活动，其余季节在低海拔活动。本文的研究结果对理解海拔、主食竹结构、营养以及大熊猫迁移活动之间的关系有重要作用，为圈养大熊猫的饲料配比提供理论依据，也为野外大熊猫的保护和规范保护区内部的人类活动提供科学支撑。

关键词: 大熊猫, 主食竹, 营养, 竹林结构, 季节迁移